Food



- about 125 F. and 145 the yeast.

Patented May 12, 1,942

UNITEDT STATES ,QPATYEN r OFFICE r'oon Sidney -Mushcr, New York, N. Y., assignor to Muslier Foundation Incorporated, New York, N. Y.,a corporation of New York No Drawing. Application November 30', 1939, v Serial No. 306,815

8 Claims. (01.99-163) This invention relates to the use of yeast, particularly brewers dried yeast, which yeast has been heated to a sufilciently high temperature to kill the yeast cells and to inactivate those organisms which produce fermentation. The yeast is desirably filtered from the beer after the fermentation of the beer has been completed and is then dried.

The yeast freed of iermentative organisms is desirably used in curing operations such as in the curing of meats and fish and particularly fatty meats'and fish, such as bacon, mackerel, salmon and tuna fish.- The yeast may also be-addedto' cream before'pasteurizing, which cream is then churned to produce butter, or to fruit ice creams and particularly to strawberry ice cream.

Beforeaddition, the yeast is filtered from the beer and is dried desirably at a temperature of over about 150 F. and preferably at some stage in the drying operation the temperature is in-- creased to approximately 200 F. in order to kill off the fermentative organisms of the yeast.

There may also be utilized the water soluble constituents contained in yeast prepared by extracting the yeast in a slightly acidified water or alcohol and then concentrated after extraction to over about 50% total solids.

The water soluble extract of the yeast which is extracted by a'slightly acidified water and at a temperature between about 125 F, and 145 Fris either before, during or after extraction rendered substantially free of fermentative organisms.

The temperature of the water at the time of the extraction should-not be in excess of about 140 F. to 145? F. norless than about 125 F. .to'

The water used should be substantially free of minerals and desirably free of iron and copper. Where the water normallyhas a pH'above 7.0,

it should be acidified to reduce the pHwPreferably, in order to obtain a clear supernatant water containing the extract, and to obtain the most desirable type of extract, the'pH of the water should be adjusted to between 4 and 7 and preferablyto about 5 to 6 by addition of a mineral acid such as hydrochloric, sulphuric or phosphoric, or an organic acid such as acetic, tartaric,

citric, etc.,.or by. the addition of acidsalts such asacid sulphates or phosphates. This adjustment may take place during or before the extrac-' tion. The pH- adjustment will also, serve to increase the rate at which insoluble material will It is quite important that the extract after 2 preparation from the between 40% and. 75% The temperature of yeast be concentrated to total solids or more,

extraction may be between tive organisms have already been killed off in However, where there still remains any live cells in the yeast, the extraction should proceed for the shortest possible time such as for less than 30 minutes at-a temperature of not in excess of about 115" F. and preferably at room temperature. I

As an example of the method of preparing such extract from yeast, the yeast is desirably first pressed to a paste containing in excess of about 30% total solids or dried or the yeast may be extracted after having been skimmed oiT the fermented beer and then pressed to remove extraneous materials. The yeast is desirably finely macerated or ground in order to expose the yeast cells which may then be subjected to asufliciently high temperature to kill off the fermentative 01'- F. provided the fermentaotherwise treated to remove the aqueous solution,

settle out leaving a clear supernatant water portion containing the extract.

Any quantity of water may be used to produce a free ilowing mixture. One part of yeastshould preferably be mixed with..a-bout 4 parts of water by weight. Other proportions may also-be used such as from i to"15 par ,.of"'water to every 1 part of yeast." I

Another ,very' satisfactory method is tor the yeast to be ground or milled with sufficient water to produce a paste and whereby the cell structure of the yeast is so broken into as to permit the maximum solubility of the water extractable substances into the water. Then the pulpy aqueous mass may be pressed or centrifuged or containing the extract. Preferably the same temperature and acidity are'employed as above. The solution may be clarified or filtered or where additional water is added, allowed to settle out.

Where the yeast-water suspension is allowed to stand for settling out, and after the 30 minute agitation and extraction period, the solution should desirably be cooled by placing it in a jacketed or coiled wt or by running water through cooling coils immersed therein or by adding cold water to the hot yeast-water suspension, so that the temperature of the water is reduced from 135 F. to from 80 F. to 105 F. and preferably to about 100 F. in order to avoid changes during the settling period. The solution thus cooled may then be treatedto remove the yeast insoluble portions. This may be accomplished by allowing the solution to settle for from 2 to 12 hours until a substantially clear unfermented supernatant liquid is formed which liquid is removed by decanting, siphoning, or similar process. 7

The solution containing the yeast may also be subjected to a continuous centrifuging whereby all undissolved material is removed as a continuous operation.

The substantially clear solution thus obtained should desirably be evaporated by vacuum disti1-' lation at about 135 F. to approximately between 45% and 75% solids and desirably to about 70% solids and to a Baum of 37. After the proper solids content has been reached, the extract should desirably be subjected to superheated steam in the vacuum pan in order to raise the temperature of the extract to 200 F. for about 10 minutes in order to sterilize it and also retain its full stabilizing properties for longer periods.

The evaporating temperature may vary, dependent upon whether vacuum or atmospheric pressure is used. Although it is desirable to use vacuum evaporation, evaporation at atmospheric pressure may also be employed. 7

The concentrated extract may also be packed in cans or other containers and sterilized at 220 F. to 250 F; for 10 to 30 minutes.

Where, due to prolonged sterilization or high heat during such sterilization, a coagulation or precipitation is formed resulting in the production of insoluble matter, such precipitate may be filtered or otherwise removed. Distilled or softened water' is desirable as the extracting medium and'will avoid, to a large degree, such precipitation and coagulation.

Where drying is desirable, the concentrated water extract may be dried on trays, preferably under vacuum and a desirable dried product will be obtained. Drum drying is; diflicult in view of the mucilaginous nature of the extract by means of which the extract adheres to the drum and cannot readily be scraped off. Spray drying may less preferably be resorted toin view of the oxidation occurring during the spray drying operation.

A small quantity of the yeast and preferably its water extract in concentrated form may be added to cream containing between 30% and 35% of butterfat in its disperse phase and the cream then churned to produce butter, in which the yeast or the yeast extract is removed with the buttermilk leaving the butter substantially free of the added yeast material but nevertheless stabilized against oxidative deterioration.

Example 1 Brewer's yeast was heated -in its moist condition to 200 F. for minutes in order to kill off the fermentative organisms. The yeast was then extracted for 1 hour using 5 parts of water to 1 part of yeast at a temperature of 135 F., and at a pH of 6, the water soluble portion being removed by filtration and then concentrated in a vacuum pan at 135 F. to about 70% solids or to a Baum of 37. 0.25% of this concentrated extract was added to a 35% butterfat containing cream and the cream then pasteurized and churned to produce butter. The butter was stored at 50 F. and compared in keeping quality with ordinary untreated butter to which no yeast extract had been added. An improvement of 1 point in the scoring of the butter was observed within 3 weeks which increased to about 1 /2 points after a 4 week period, over the untreated butter score.

The yeast or yeast extract may be added in any desirable amount but generally less than 2% and preferably under .5% is added. For all normal purposes, as] little as from 0.05% to 0.5% may be added to. cream in the manufacture of butter. 1

Similarly thegyeast and its extract may be added in the brining or curing of meats, fish, olives and other food products and particularly of such fatty meats and fish as bacon, mackerel, herring, sardines, salmon and tuna fish.

For example, in the brining of mackerel or in the curing of fatty bacon, from 0.05% to 2% and preferably under about 1% of the yeast or its water extract may be added to the brine solution or with the other curing ingredients and raneidity of the bacon as well as of the salt mackerel willbe very materially retarded.

Example II The extract prepared as forExample I was admixed with salt in an amount of 5% against the weight of the salt. The salt containing the yeast extract was used in the curing of mackerel by rubbing the salt-extract combination over the mackerel and using 60% of the treated salt against the weight of the mackerel. The mackerel was observed at regular intervals in comparison with mackerel with which salt alone had been used in the curing and it was observed that the mackerel cured with the.treated salt was free of raneidity for a period of over 3 months, whereasthe mackerel cured with the untreated salt kept free from raneidity for a period of only about a month and a half. a

The yeast extract may also be utilized in an amount of between about 1%. and 15% on the basis of its total weight against the weight of the salt used in the brining or curing operations.

Particularly in the manufacture of the fruit- To a strawberry ice cream mix was added 0.1% of a fermentative organism-free yeast powder. The strawberry ice cream mix was then frozen and held in storage at 15 F., being tasted at regular intervals for off-flavor developments. It was observed that the strawberry ice cream containing the yeast powder was substantially free of off-flavor development for a period of 5 weeks whereas a lot of strawberry ice cream to which yeast powder had not 'been added showed the off-flavor development within about 2% weeks.

The extract of yeast mayalso be added to sizing baths used for the sizing of textiles, paper and board and particularly where the paper or board is used as wrappers for butter, lard, sliced bacon, biscuits and crackers.

It has been particularly found that where the 2,282,793 yeast or its extract is added to an organic mate rial subject to oxidation and that organic mate rial containing the yeast or its extract thoroughly dispersed therein subjected to an elevated temperature in excess of about 170 F. and desir-,

ably to about 250 F. or above, marked improve-' ment in keeping qualities is obtained.

For example, the yeast or its extract may be added to chopped hog fat and the chopped hog fat-then rendered at a temperature of about 250 F. orabove, or used in the rendering of tallow, oleo oil or lard at the elevated temperatures of rendering, or the extract may be added to cream which is then heated to about 180 F. and churned to produce butter.

In the manufacture of strawberry ice-cream, it is desirable to add the yeast or its extract to the strawberry ice cream before the ice cream mix has been heated to 145- F. or above and it is particularly desirable for the yeast to be added to the cream used in the manufacture of the ice cream and the cream then heated to about 170 F. to 180 F. and such cream then used in the manufacture of the strawberry ice cream. In the treatment of glyceride oils and fats such as lard, tallow, oleo loil, cottonseed oil, corn oil, soya bean oil, castor oil, cod liver oil, tea seed oil, olive oil or other animal or vegetable oil or fat either irisubstantially crude, refined .or hydrogenated condition, 'it'is desirable to use the. finely divided yeast itself, adding the yeast, with its fermenting organisms having already been killed off, in aux-amount of between 0.05% and 5% and thoroughly admixing the yeast in the oil or fat.

Example IV powder. The yeast powder was thoroughly mixed in the lard and the lard tested on the Swift Stability Apparatus by means of which air is bubbled thorugh a 20 cc.-sample of laid at 208- F. until rancidity is observed. The results obtained were as follows: r

I Rancid after- Untreated lard 1 hour Treated lard 4 hours Ezample v i Chopped hog fat was rendered at 260 F. for

3 hours. To the chopped hog fat was added before rendering 0.1% of fermentative organismfree brewers yeast powder and thoroughly admixed with the chopped hog fat in the rendering kettle.- The lard which was rendered was compared in keeping quality with lard prepared from r'a' 'similar lot of chopped hog fat to which no yeast powder had been added.

Preferably, however, the fermentative' org'anisms have been killed off.

As indicated above, where the yeast extract or the yeast powder with its fermentative organisms killed ofl has been added to a substantially pure glyceride such as to lard, cottonseed oil, olive oil, etc., it is desirable for the oil following the addition of the yeast thereto to be subjected to an elevated temperature in excess of about 170 F. and desirably to 250 F. or over.

, Another feature of the present invention is that the yeast powder or its extract may, for example, be dissolved or dispersed in a concentrated sugar solution such as in molasses, as refinery or crude blackstrap or sorghum or beet molasses, and the molasses or concentrated crude sugar solution containing the yeast then serving as the continuous phase for the dispersion of a vitamin containing oil therein such as for dispersing cod liver oil, halibut liver,.oih or other vitamin containing oil in the'molassescontaining the yeast. Under these circumstances,the cod liver oil or other. vitamin containing oil is. very materially improved in keeping quality. -For example, a

mixture may be prepared comprising 5% of. the

yeast in molasses andthe molasses containing the. 5% of yeastthen used as the aqueous continuous phase for the'dispersion of about 15% of cod liver oil which cod liver oil may be homogenized in .the molasses. containing the yeast.

Desirably, the mixture is then subjected to an elevated temperature of 250 F. or above.

In the preparation of the water extract of the yeast, where desired a carrier may be employed in'the drying of the extract. For example, the concentrated water extractof the yeast may be mixed with condensed skim milk, on the basis of using from 5% to %by weight of the extract (on its solids basis) against the solids weight of the skim milk and the thoroughly mixed combination of the extract and skim'milk dried on a drum drier orotherwise dried. The skim milk absorbs the gummy characteristics of the extract and permits much easier drying than where the extract is dried alone. v

There isobtained a combinedaction' of the milk ingredients with the extract to further increase the stabilizing action of the extract, The

drying may be done preferably one. hotroll and ,the dried film scraped off after drying. less preferably the mixture may be into a heated chamber. i I This-dried combination'ma'y then very desirably be utilized for addition to dairy products such as for addition to an ice cream mix, to cream in the manufacture of butter, or to market milk in an amount-ofbetween'0.1% and 5%, for example,o r for use in the manufacture of sausage or other oxidizable food compositions. Where desired, as littleas 0.5 of theextract on its solids basis may be combined with the skim milk on'its solids basis.

Other carriers may also be employed and particularly salt and sugar. The extract may, for

dried by spraying example, be mixed with salt or sugar using from fermentative organisms will have been better preserved during normal distribution or storage periods and without requiring the same care that is needed where the yeast itself is to be held.

1% to 20% of the 'extractand 99%to of the salt or sugar and preferably applying the concentrated extract to the sugar or salt crystals byspraying such extract on the crystals while they are kept at above F. and desirably at between 250 F. and 300 F. so that the extract dries on the surface of the crystals of the salt or sugar.

For example, as the salt crystals leave the kiln at 2752? the extract containing 130% water may be heated to 170' I", and sprayed on the salt crystals, applying 2% on the solids basis to the salt in this manner, thereby obtaining a completely.-

By; applyingthe e ract to sugar, particularly,

' either in crystalline form .or as a concentrated solutio a sugarepreparation is obtained which may be utilizedpal'flcularly when subjected to elevated temperatures in oxidizable food compositions, such as for addition to dairy products, candies and confections, beverage such as Coca- Cola and other fruit orange juice, lemon juice, in .the cannins of fruits, etc., and particularly. where the sugar containing the extract is heated, to a temperature of about 250 F. or above after addition to the food. r

Similarly, the treated salt may manufacture of butter in place of ordinary salt or in curing or brining operations such'as in the curing or,-brining of meats, fish and olives and particularlyo f. fatty meats and fish; I

;,Alcohol may also be used as the extractant beus'edinthc as "mushrooms and their extract prepared as described. p v I a It is desirable for the-yeast orits extract to be added in an amountinsufllcient' to produce any yeast odor or flavor ln the food, such as in the butter, bacon ,or strawberry ice cream, and gen-' erally the amount will be less than about.

' Zymase may also be utilized, particularly in its inactive form and after having been subjected to the elevated temperature of inactivation, and

preferably in combinationwith a sugar and where subjectedto'an elevated temperature of over 170 and desirably overi250 F. after addition to the oxidizable composition.

,The present application is a continuation in part of applications, Serial No. 301,758 filed 0ctober 28; 1939, now Patent No. 2,198,205 and Serial No. 301,757 filed October 28, 1939, now

Patent No. 2,198,206 and through said applications continues the subject matter of applications,

from .theyeast-which has been freed of fermen- Y tative organisms and particularly the lower molecular weight alco'hols which have been slightly acidifiedv and with or without a small quantity of water also present at the time of extraction.

The extract'may also be mixed with fully water miscibleor partly water miscible organic solvents such as, for example,.acetone, or alcohols and particularly the higher molecular weight aliphatic alcohols such as-but'yl alcohol, toprecipitate and remove undesirable, materials. If desired, it is also possible; although less preferable, to use a mixture of water and these organic solvents as "extracting agents, preferably in slightly jacidifi'ed' condition. 01', on the other hand; .the organic solvents themselves may be utilized as the extractant following which they may be evaporated to obtain the concentrate or mixed with water to precipitate therefrom materials not desiredin the final concentrate.

The yeast that is utilized in accordance with this invention is preferably brewer's yeast or yeast obtained during the manufacture of beer although yeast obtained from thednanufacture 'of alcohol by molasses fermentation or in distillery operations may also be utilized. Both top yeast and bottom yeast" may beemployed Dried grains containing high proportions of yeast but freed of fermentative organisms or their extracts may also be employed in a similar manner although brewers yeast is preferable.

h It is also possible to form combinations in dry or paste form of the yeast or its extracts with a phosphatide of animal or vegetable origin such as. lecithin or cephalin and/or with a sugar such as dextrose or sucrose in amounts of from 1 to 5 parts of the yeast or its extract with from 5 to 1 parts of the phosphatide and/or sugar and then after adding such combination to an oil, particwlarly a glyceride oil oroil containing composition, followed by heating to over 170 'F, and preferablyto 250 F. in order to obtain enhanced stability. v

In lieu of or in possible, but less preferable. to utilize fungi such addition to the use of yeast, it is Serial No. 268,341 filed April 17, 1939, now Patent No. 2,176,024, Serial No, 249,990 filed January 9, 1939, now Patent No. 2,176,027," and Serial No. 229,296 filed September 10, 1938, now' Patent No. 2,176,028.

-Having described my invention,

claim is 1. A method of treating food compositions to stabilize them against oxidative deterioration which comprises adding theretoa relatively small what I proportion of a material selected from the group consisting of inactivated yeast and its water and .alcohol soluble extracts.

2. A method of treating food compositions to stabilize them against oxidative deterioration activated yeast. c

which comprises adding thereto a relatively small proportion-of a slightly acidified water soluble extract of inactivated yeast.-

3. A method of treating glyceride oil containing food compositions to stabilize them against oxidative deterioration which comprises adding thereto a small proportion of finely divided inactivated yeast.

4. A method of treating a glyceride oil to stabilize-it against oxidative deterioration which comprises adding thereto finely divided dried in- 5. A method of treating food compositions to stabilize themagainst oxidative deterioration which comprises adding--- thereto a relatively small proportion of a material selected from the group consisting of inactivated yeast and its water and alcohol soluble extracts, and then heating the composition to a temperature in excess of F. whereby enhanced stabilization is obtained. r I

6. A food compositionstabilized against oxidative deterioration, said food composition containing a small amount of a material selected from the group consisting of inactivated yeast and its water and alcohol soluble extracts as the stabilizing agent,

7. A glyceride oil containing food composition stabilized againstloxidative deterioration, said food composition containing a small amount of inactivated yeast asthe stabilizing agent.

8. A glyceride oil stabilized against oxidative deterioration, said glyceride oil containing a small amount of dried inactivated yeast as the stabilizing agent.

SIDNEY MUSHER. 

